Method of judging suitability of raw barley for feedstock for malt production according to staining technique

ABSTRACT

An object of the present invention is to provide a method for evaluating the physical strength of husks of a barley ingredient for malt manufacture. Barley kernels with husks are disposed in a sulfuric acid solution with a concentration of approximately 40% to 60%, and are agitated for a prescribed time (e.g. approximately 1 hour) using a stirrer bar or the like. After agitation, the barley kernels are treated with a mixed liquid of Methylene Blue and Eosin, and the degree of peeled husk (remaining degree) is examined by referring to the degree of dyed barley kernels, to thereby evaluate the physical strength of the husks of the barley kernels.

TECHNICAL FIELD

The present invention relates to an evaluation method regarding thesuitability of barley, being used for malting barley for maltmanufacture, and being the malt ingredient for manufacturing beer,low-malt beer, distilled liquor, and the like.

Further, the present invention relates to an evaluation method duringselection of a variety•line in growing a barley variety for breeding abarley variety having a husk with desirable physical strength.

BACKGROUND ART

Barley, being the malt ingredient in manufacturing beer, low-malt beer,distilled liquor and the like, becomes the ingredient for maltmanufacture by undergoing processes such asharvest•selection•transportation, and having impurities, foreignsubstances, different type kernels and the like removed therefrom.Barley kernels are subject to various physical forces during suchprocesses in respective stages or during transfer in-between the stages.During this, the husk disposed at the outermost layer of the barleykernel may in some cases peel off from its barley kernel due to thebarley kernels being brushed against each other or barley kernels beingmechanically struck against hard objects such as metal ones.

Such a barley kernel having its husk peeled off will, in upcomingprocesses, be subject to a harsher force than that of a barley kernelwhich is not peeled. In this case, a barley kernel whose embryo is notcovered by the husk is particularly vulnerable to embryo damage, therebypreventing the peeled barley kernel from sprouting normally.

Further, in the beginning of malt manufacture, barley kernels are firstsoaked in water. Barley kernels containing moisture will, however,soften and thereby be more liable to receive damage compared to dryones.

Malt can be manufactured only after biological•physiological•biochemicalreactions take place to sprout the barley. However, barleys that havefailed to sprout not only are unable to malt, but also cause corrosionduring the sprouting stage, adversely affect normal sprouted barley, andresult in a final product with a malt quality that is unsuitable for itsintended use.

Since evaluation of whether the barley ingredient is suitable for maltmanufacture was conventionally performed through macroscopic testing byengineers experienced in malt manufacture, there was a discrepancy inthe evaluation results depending on the individual performing theevaluation, and the accuracy of the results was not always high.

In respect of barleys aimed to be purchased for malt manufacture, thepresent invention enables distinct evaluation of whether the barleys aresuited for malt manufacture with a scientific method without relying onexperience by using a portion of the barleys prior to their purchasing.Further, the present invention provides a method of selecting kernels ofbarley used in breeding a malt, which have a husk of high physicalstrength, suited for malt manufacture.

DISCLOSURE OF INVENTION

The above-mentioned problems can be solved with the following processesaccording to the present invention.

One embodiment of the present invention is a method having acharacteristic in which solubilization of husk is performed by uniformlysampling barley, aimed to be used as an ingredient, and treating theobtained sample ingredient with sulfuric acid. Then, the barley kernelhaving the solubilized husk is agitated under prescribed conditions.Observations are made on the degree of peeled husk or the degree ofremaining husk of the barley kernel subsequent to the agitation.According to the results, the physical endurance of the husk of thebarley kernel is evaluated. Thereby, physical strength of the husk ofthe barley can be objectively determined. Therefore, a high qualitybarley ingredient for malt manufacture aimed for manufacturing fermentedmalt beverages can be provided.

Another embodiment according to the present invention allows barleykernels with peeled off husks and also the peeling degrees of the barleykernels to be distinctively determined by performing a dyeing process tobarley kernels that have undergone the above-described solubilizationwith sulfuric acid and agitation. Thereby, physical strength of huskscan be evaluated with higher accuracy. Further, since the portion atwhich husks remain and the portion at which husks are peeled aredistinguishable by color, observation through the naked eye will beeasier, and automatic quality distinction will also be possible by usingimage signals of a camera tube and the like.

Furthermore, in another embodiment according to the present invention,the proportion of barley kernels having 80% or more of its husk for asingle kernel being peeled to the total barley kernels is used as acriterion for evaluating whether the barley, having undergone husksolubilization and agitation according to the present invention, issuited to be the barley ingredient for malt manufacture. Thereby, thequality of barley ingredient can be classified according to a uniformcriterion, and high quality malt manufacture can be achieved.

A further embodiment according to the present invention is a methodusing the above-described barley ingredient evaluation method duringselection in growing a barley variety and breeding the barley variety.

All of the barley ingredient evaluation methods according to the presentinvention may be employed for selection of seeds used in breedingbarley, as an alternative for straightforwardly employing the methodsfor malt manufacture. Thereby, barley that has a husk with strongphysical strength can be bred, and a high quality barley ingredient formalt manufacture can be provided.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a view for explaining a cross-sectional structure of barley;

FIG. 2 is an image showing an example of malting barley “RYOFU” with amethod according to the present invention applied;

FIG. 3 is a view showing an example of malting barley “FRANKLIN” with amethod according to the present invention applied; and

FIG. 4 is a view showing an example of barley “HARRINGTON” with a methodaccording to the present invention applied.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of an evaluation method for evaluating the physical strengthof a barley husk according to the present invention are described indetail below.

The barleys, the reagents, and the testing methods employed in theembodiments according to the present invention are given below. Barley

“Ingredient and Reagent”

1. Ingredient

1-1: Malting barley “RYOFU” (Produced in Hokkaido in year 2000)

1-2: Malting barley “FRANKLIN” (Produced in Australia in years1999-2000)

1-3: Barley “HARRINGTON” (Produced in Canada in year 1998)

2. Reagent

2-1: 50% Sulfuric Acid

2-2: 0.2% Methylene Blue+0.2% Eosin Y (98% Methanol Solution)

“Method”

(1) Sample approximately 4 g of barley (approximately 100 kernels) froman ingredient lot. Add the samples to a 200 ml beaker containing 80 ml(room temperature) of 50% sulfuric acid. Agitate for 1 hour at 150 rpmby using a 5 cm long stirrer bar and make the husk easy to peel off.(2) After the agitation, dye the barley, which is washed with water, for1 hour with 0.2% Methylene Blue+0.2% Eosin Y (98% Methanol Solution).Remove excess dye by washing with water.(3) The husk and pericarp remaining after the sulfuric acid process aredyed to a dark blue color, and the embryo and the scutellum is dyed to ared-pink color. Exposed endosperm is not dyed and is a white color.

FIG. 1 shows a cross-sectional structure of a barley kernel where thekernel is in a state completely covered by a husk.

FIGS. 2, 3, and 4 are photographs showing the results of performing themethod on barley “RYOFU”, barley “FRANKLIN”, and barley “HARRINGTON”,respectively. “Method of evaluating ease of peeling of barley husk”

When barley kernels, having been treated with sulfuric acid, are dyedwith the two dyes, the remaining husk and pericarp are dyed to a darkblue color, and the embryo and the scutellum are dyed to a red-pinkcolor, as described above.

It is believed that the reason why the husk and the embryo are dyed todifferent colors in the foregoing manner is because the large amount ofcell membrane in the husk causes it to be dyed to blue color, and thelarge amount of plasma in the embryo (surface) causes it to be dyed tored-pink color.

Accordingly, in order to observe the physical endurance of the husksubjected to sulfuric acid treatment and agitation, the portion wherehusk is peeled and the portion where husk remains can be distinctivelyconfirmed by counter staining the treated kernels with the two dyes.Furthermore, whether the essential embryo, in particular, is exposed canbe distinctively determined depending on whether the embryo is dyed tored-pink color (embryo; eosin-Y).

The photograph in FIG. 2 shows barley “RYOFU” dyed with the presentmethod. “FRANKLIN” (FIG. 3) and “HARRINGTON” (FIG. 4), which are said tobe varieties susceptible to husk peeling, are shown for comparison. Asis apparent in the photographs, “FRANKLIN” lacks physical endurance ofhusks, and a large number of kernels being dyed to white and red-pinkcolor have been observed more in “FRANKLIN” than in other samples.

Here, in the present embodiment, the ratio of peeled husk, after beingsubjected to the treatment according to the present invention (peelratio), is obtained and quantified as an index representing the physicalstrength (endurance) of husk. That is, after sulfuric acid treatment andagitation, the proportion (%) of kernels having 80% or more of husk fora single kernel being peeled to the total number of kernel samples isobtained and quantified as peel rate R, to thereby serve as an index ofphysical strength of the husk.

In the above-described example of performing the method on the 3varieties of barley, “RYOFU” produced in year 2000 (FIG. 2) had a 12%peel ratio. On the other hand, “FRANKLIN” produced in year 2000 (FIG. 3)had a 40% peel ratio. Further, “HARRINGTON” produced in year 1998 had an18% peel ratio.

Accordingly, by obtaining the peel ratio and using it as an index of thephysical strength of the husk, objectiveness can be attained indetermining whether the barley ingredient is suited for maltmanufacture, and accurate quality control of the barley ingredient canbe achieved.

It is to be noted that, in the present embodiment, according to thecriterion for evaluating the barley ingredient with respect to the ratio(%) of kernels having 80% or more of husk (embryo side) being peeled, itis evaluated that {circle around (1)} for 20% or less: no problems,{circle around (2)} for 20% to 35%: caution required in use, and {circlearound (3)} for 36% or more: unsuitable for malt manufacture. These aredefined by relating the results based on experience with respect to theresults of peel ratio (%) according to the present method.

It is to be noted that, obviously, even where the same barley is used,the degree of peeling that the barley kernels experience will bedifferent depending on the equipment that is used.

Accordingly, with use of the present method, prior to being accepted bya factory, the degree of the physical endurance of the husk of thebarley kernels in each acceptance lot can be easily distinguished andobjective evaluation results can be attained, thereby providing for highquality malt manufacture.

It is to be noted that, although approximately 100 sampled kernels areadded to a 200 ml beaker containing 80 ml (room temperature) of 50%sulfuric acid and agitated for 1 hour at 150 rpm by using a 5 cm longstirrer bar in the above-described example, treatment conditions are notto be limited to such. For example, the concentration of the sulfuricacid may range from approximately 40% to 60%. Further, agitationconditions, such as rotation count or agitation time, may differdepending on the number of sampled kernels with respect to the volume ofthe sulfuric acid solution, and, therefore, may be changed accordingly.Nevertheless, since observation of the endurance of agitated husk isnecessary, an accurate evaluation cannot be executed if agitation timeis too short. Therefore, the preferred agitation time is more or less 1hour (approximately 40, 50 minutes to 60, 70 minutes).

Further, although the above-described example is explained as a methodfor evaluating the degree of the physical strength of the husk of thebarley ingredient before being accepted into the malt manufacture stage,the evaluation method is not limited to evaluating barley ingredientthat is straightforwardly used in barley manufacture, but can obviouslybe employed in evaluating suitability in selecting seeds for growing abarley variety. For example, a barley variety, where 20% or less is theproportion (%) of kernels having 80% or more of husk (embryo side) beingpeeled, may be chosen as a seed for breeding a barley variety, tothereby breed a barley variety suitable for malt manufacture.

With the present invention, the physical strength of the husk of barleykernels can be objectively determined, and therefore, a high qualitybarley ingredient for manufacturing malt for fermented malt beveragescan be provided.

Further, by performing the dyeing process on barley kernels that haveundergone solubilization with sulfuric acid and agitation, barleykernels with peeled husks and the degree of the peeling can bedistinctively determined.

Further, the proportion (%) of kernels having 80% or more of husk beingpeeled, is employed as a criterion for evaluating whether barley, havingundergone husk solubilization and agitation, is suitable for maltmanufacture. Thereby, the quality of barley ingredient can be classifiedaccording to a uniform criterion, evaluation can be performedobjectively, and high quality malt manufacture can be achieved.

Further, the evaluation method of the physical strength of the husks ofkernels according to the present invention can be employed in selectionfor growing a variety, to thereby breed a barley variety suitable formalt manufacture.

1. A barley kernel evaluation method comprising: disposing barleykernels having husks in a sulfuric acid solution having a 40% to 60%concentration; agitating the solution having the barley kernels disposedtherein for a prescribed time; treating the barley kernels with a mixedliquid of Methylene Blue and Eosin subsequent to the agitation;observing the degree of which the dyed barley kernels have a husk and apericap dyed a dark blue color, an embryo and a scutellum dyed ared-pink color, and an endosperm not dyed and a white color; determininga proportion R, R being the proportion of (a) an amount of barleykernels having 80% or more of the husk being peeled and not being dyed adark blue color to (b) an amount of the total barley kernels; andevaluating whether or not the barley kernels are suited for maltmanufacture based on proportion R.
 2. The barley kernel evaluationmethod according to claim 1, wherein when the proportion R is 20% orless, the barley ingredient is evaluated as usable for malt manufacture;when the proportion R is 20% to 35%, the barley ingredient is evaluatedas requiring caution during use; and when the proportion R is 36% ormore, the barley ingredient is evaluated as unusable for maltmanufacture.
 3. A method of breeding a barley variety comprising:disposing barley kernels having husks in a sulfuric acid solution havinga 40% to 60% concentration; agitating the solution having the barleykernels disposed therein for a prescribed time; treating the barleykernels with a mixed liquid of Methylene Blue and Eosin subsequent tothe agitation; observing the degree of which the dyed barley kernelshave a husk and a pericap dyed a dark blue color, an embryo and ascutellum dyed a red-pink color, and an endosperm not dyed and a whitecolor; determining a proportion R, R being the proportion of (a) anamount of barley kernels having 80% or more of the husk being peeled andnot being dyed a dark blue color to (b) an amount of the total barleykernels; evaluating whether or not the barley kernels are suited formalt manufacture based on proportion R; selecting barley kernels fromthe evaluation results; and breeding the selected barley kernels.
 4. Themethod of breeding a barley variety according to claim 3, wherein theselected barley kernels have the proportion R evaluated as 20% or less.